/Engine/Source/Runtime/Datasmith/DatasmithCore/Public/DatasmithUtils.h
Gets the file name and its extension. In case of extension like asm.1, the return name is the part before the full extension (asm.1) The right part of extension must to be a numeric value
static void GetCleanFilenameAndExtension ( const [FString](API\Runtime\Core\Containers\FString) & InFilePath, [FString](API\Runtime\Core\Containers\FString) & OutFilename, [FString](API\Runtime\Core\Containers\FString) & OutExtension )